This invention relates to the bulk collection of texturized strand, and in particular, to a method and apparatus for the bulk collection of texturized strand. The invention is useful in the production of sound absorbers that may be used to reduce noise emissions of a vehicle.
This invention relates to the bulk collection of strand, and in particular, to the bulk collection of texturized strand. A strand of glass filaments is typically formed by attenuating molten glass through a plurality of orifices in a bottom plate of a bushing. The filaments are attenuated by applying tractive forces to the streams of glass, so as to attenuate the streams. The filaments are coated with a size or binder material which serves to provide a lubricating quality to the individual filaments to provide them with abrasion resistance. The glass filaments are sized with the size material substantially immediately after they are formed. The filaments are gathered in parallel relationship to form a strand.
In conventional filament forming systems, the streams of glass have been attenuated by winding the filaments on an exterior of a rotating tube. The strand of filaments is wound on the tube as a cylindrical package. The winding device with the rotating tube pulls the filaments and collects the strand.
Instead of winding the strand around a rotating tube, the strand may be gathered into a container. The strand is typically collected in a container when it is attenuated by a pulling device such as mating wheels or a pair of belts. A bulk collection of strand can be easily shipped and used in subsequent processes.
Texturized strand is continuous strand that has been expanded or texturized. The fibers in the strand are separated to give the strand a full, wool-like appearance. Texturized strand has good acoustic and thermal insulative properties. Texturized strand is typically used in sound absorbers.
Sound absorbers are used to reduce noise emissions and have numerous applications, for example, a muffler for a vehicle. A conventional sound absorber often includes a sound absorbing material, such as fiberglass wool, that is disposed between a housing and an inner tube and that dampens or attenuates noise in the gas flowing through the muffler.
One process for manufacturing a sound absorber with texturized strand is to directly fill the sound absorber with the strand. U.S. Pat. No. 4,569,471 to Ingemansson et al. (xe2x80x9cIngemanssonxe2x80x9d) relates to a process and apparatus for feeding lengths of continuous glass fiber strands into a muffler outer shell such that the fiber strands are expanded into a wool-like material inside the shell. The manufacturing process in Ingemansson requires that expensive apparatus be available at manufacturing locations where muffler shells are filled with sound absorbing material. In addition, some muffler types have intricate shapes and are not easily filled with sound absorbing material such that the sound absorbing material uniformly fills the entire inner cavity of the muffler shell.
A need exists for an inexpensive way to collect texturized strand in a bulk form which permits the subsequent use of the strand. A need also exists for an inexpensive way to collect texturized strand so that it can be pulled from the container in which it is collected.
The shortcomings of the prior art are overcome by the disclosed method and apparatus for collecting texturized strand. The apparatus for collecting texturized strand includes a texturizer for expanding a continuous strand of glass fibers into a texturized or wool-like product, a container for collecting the texturized strand, and a device establishing a pressure differential between an interior region of the container and a region external of the container.
The texturizer includes a nozzle to which a supply of compressed air and a continuous strand are fed. The compressed air advances the strand of glass fibers through the nozzle and expands the strand so that the filaments are spread apart, thereby giving the strand an expanded shape or form.
The pressure differential establishing device includes a vacuum apparatus for drawing air and a screen through which the air flows. A container is placed on the screen. In the preferred embodiment, the container is a corrugated box that has upper and lower closures or flaps. The lower flaps are folded back, thereby revealing an opening in the bottom. The container is coupled to the pressure differential creating device so that the container opening is in communication with the screen.
The nozzle is manipulated to direct the strand from the outlet of the nozzle into the container. The system may include a deflector assembly for changing the direction of the texturized strand as it is directed into the container.